Maker Pro
Maker Pro

AOC 919Vwa+ Displays Horizontal lines

Bumblebee001

Jul 19, 2013
76
Joined
Jul 19, 2013
Messages
76
Hi Guys (& Dolls),

I have another issue this time with an LCD monitor model AOC 919Vwa+ conntected via DVI.

Upon powering up the picture is abnormal - jittery and rather broken up but it gradually settles to display a usable screen with several horizontal white lines along the lower part of the screen when the picture stabilizes. The image is also displaced slightly upwards so that calibrating the touch screen I have added will give me reference points going beyond the upper margin of the screen. I am including a photo of the screen but do have a short video to show how it actually lights up on powering it on (https://mega.nz/#!BIYliRAb!zODNa96e_STA5TL-5BqWpMRUIAxAMx0uxwdoiWoIZSQ).

I did check the inner electronics and no swollen capacitors are visible.

This is part of a set-up of an electronic organ I built that has a dedicated motherboard, videocard + 2 monitors (VGA and DVI) each fitted by me with a touch-screen, onboard sound card, 3 sata hard drives, optical drive, 3 manual MIDI USB keyboards and a MIDI pedal board I made using an Arduino module20170505_202659.jpg . I have had to use a USB hub to connect touch screens and a wireless network adapter.

I hadn't used this organ at all for some 6 years and before played it sparingly as I went along building it. Only lately did I start to play it again having had to reinstalled Windows 7 ultimate because my previous installation was shutting down or going into sleep mode often, sometimes as often as some seconds and eventually led to corruption of the OS as it shut down during a long windows update. Now the set up is stable and no more unexpected interruptions.

I am using the same cable and software & drivers seem to be up-to-date. The issue may well coincide with the re-installation of windows and swapping of the several USB connections to get everything working properly.

Any ideas of what could be wrong with this display?

Mark
 

Harald Kapp

Moderator
Moderator
Nov 17, 2011
13,743
Joined
Nov 17, 2011
Messages
13,743
Have you checked with another monitor to ensure the problem lies with the monitor, not the graphics card, the DVI cable or the drivers (as you mentioned to have issues with th einstallation of the operating system)?
 

Bumblebee001

Jul 19, 2013
76
Joined
Jul 19, 2013
Messages
76
Have you checked with another monitor to ensure the problem lies with the monitor, not the graphics card, the DVI cable or the drivers (as you mentioned to have issues with th einstallation of the operating system)?
Another monitor works perfectly fine with the same DVI and power cables. It must therefore be the monitor that has a fault.
 

davenn

Moderator
Sep 5, 2009
14,264
Joined
Sep 5, 2009
Messages
14,264
Another monitor works perfectly fine with the same DVI and power cables. It must therefore be the monitor that has a fault.

A 99% probability that it is an LCD panel fault. I see this thing on a weekly basis with gear coming into my workshop and it is pretty much always the LCD panel.
The chances of you buying the panel cheaper than just buying a new monitor is unlikely ... but you can try :)


Dave
 

Bumblebee001

Jul 19, 2013
76
Joined
Jul 19, 2013
Messages
76
It is a great shame as this monitor has hardly been used at all. In fact it was bought much later than the first (Acer) which still works well and by the time I decided to get this second monitor, the suppliers in my country did not have an identical monitor in stock much to my great disappointment and therefore had to contend with the AOL they had.

If it is the LCD panel, would the image be so distorted for the first few minutes and then settle down after several minutes? The horizontal lines are greater in number initially but then decrease to a smaller number towards the bottom. I am not knowledgeable at all in electronics and I shall not dare argue with you but I find it difficult to understand the odd behaviour and the lines being as being caused by a faulty panel rather than a defective component on the board. Once again I have no technical knowledge and I guess I shall have to accept your word for it.
 

davenn

Moderator
Sep 5, 2009
14,264
Joined
Sep 5, 2009
Messages
14,264
If it is the LCD panel, would the image be so distorted for the first few minutes and then settle down after several minutes?

sometimes, but not usually. some I see will be there when cold and completely gone when warmed up .... others the other way around,
others will stay faulty permanently

LCD faults I see regularly ( not caused by a fault with the monitors' main board(s) ) .....

1) totally blank
2) half and half blank and working, either vertically or horizontally
3) several to multiple lines across the screen either vertically or horizontally ( like yours)
4) inverted colours
5) a missing colour(s)

to name a few


Dave
 

Bumblebee001

Jul 19, 2013
76
Joined
Jul 19, 2013
Messages
76
I have submitted a complaint to the company's branch in Germany (probably where this monitor was imported from by the local retailer) hoping some remedy or replacement as this must therefore be a latent defect. I am not holding my breathe and not so naive that the company will remedy the issue but worth a try.

If I get no satisfactory solution, AOC monitors will be definitely crossed off my list of preferred brands and will never recommend them.
 

Bumblebee001

Jul 19, 2013
76
Joined
Jul 19, 2013
Messages
76
One additional observation: the monitor is listed on my system as a generic non-PnP monitor and trying to update driver from a CD that came with, I keep getting that the latest driver is installed. Besides the CD does not have any driver for Windows 7 (only 2000, ME, XP and Vista).

Could there be something here that might be contributing to the problem?

I did uninstall the device, rebooted and re-added. Still being listed as generic!
 

davenn

Moderator
Sep 5, 2009
14,264
Joined
Sep 5, 2009
Messages
14,264
I have submitted a complaint to the company's branch in Germany (probably where this monitor was imported from by the local retailer) hoping some remedy or replacement as this must therefore be a latent defect. I am not holding my breathe and not so naive that the company will remedy the issue but worth a try.

yup worth a try :)

ohh and it's "hold you breath" ..... breathe is what you do, as in breathe in and out ( pronounced differently) ;)


Could there be something here that might be contributing to the problem?

I did uninstall the device, rebooted and re-added. Still being listed as generic!

not likely, 99% probability that isn't a software problem
 

Bumblebee001

Jul 19, 2013
76
Joined
Jul 19, 2013
Messages
76
yup worth a try :)

ohh and it's "hold you breath" ..... breathe is what you do, as in breathe in and out ( pronounced differently) ;)




not likely, 99% probability that isn't a software problem

Hahaha... thanks. What we call a lapsus! I should know better!
 

Bumblebee001

Jul 19, 2013
76
Joined
Jul 19, 2013
Messages
76
I reduced the number of lines and jitteriness by reducing the resolution of the screen through videocard software and reducing the refresh frequency to 40Hz. lower settings worsened the image as did higher settings.
 
Top